The International Olympic Committee will decide Saturday on the host of the 2020 Summer Games. Istanbul, Madrid and Tokyo are vying for the honor.

As our reporters noted on Morning Edition, these are all world-class cities with strong selling points, but they also face some serious challenges.

Istanbul

NPR's Peter Kenyon reported this morning on some of the preparations in Istanbul, where there is optimism surrounding the games.

Turkey would be the first predominantly Muslim country to host the Olympics. But there are hurdles, too: "Violent crackdowns on street protests thrust Istanbul into the headlines this summer, and a doping scandal has rocked the country's sporting federation," Peter says.

And, he says, environmentalists and urban planners say the last thing Istanbul needs in more mega-projects.

Tokyo

Tokyo last hosted the games in 1964. Reporter Lucy Craft says the Olympics are a chance for Japan to show "it still matters."

Tokyo is one of the richest cities in the world, but the Japanese economy has barely recovered from nearly two decades of low growth. Lucy says:

"Saddled with a shrinking, graying population, living uncomfortably in the shadow of an ascendant China, Japan is anxious to prove it remains a contender. On the practical side, the Games were seen as a much-needed boost to tourism, for a country that is way off the beaten track and expensive to visit."

Madrid

Reporter Lauren Frayer says Madrid's residents are excited at the prospect of winning the games – amid a recession that has hit the country particularly hard.

"Madrid is littered with half-built stadia, housing and public parks left over from the construction boom-and-bust — which would be repurposed for the Olympics. Blanco says 80-percent of the infrastructure Madrid needs for the Games is already in place. So its bid comes in at around 3 billion dollars — one of the cheapest in Olympic history."

Spain last hosted the summer games in 1992, when they were held in Barcelona.

Is It Worth It?

The jury's out on whether mega-sporting events help an economy.

Writing in Quartz, Sidin Vadukut argues that major sporting events are bad for a country's economy. Citing a working paper from Oxford University's Said Business School, he noted every single Olympics in the past 50 years had overrun initial cost estimates by an average of 179 percent – yes, you read that correctly. (Though the British government says the 2012 games came in under budget).

"Instead of leaving a trail of broken economies and decrepit stadiums in its wake, why don't [soccer's governing body] and IOC simply do what so many other sporting bodies do: opt for permanent or semi-permanent venues," he wrote.

What do you think? Would you want you city to host a major international sporting event or build an arena with public financing? Let us know in the comments below.

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